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in assembler file I have
// RO_BASE = 0x78000000
DCD FooEntry - . + .
what does it mean "minus dot plus dot"?
The 'dot' means the address of the instruction or data. it is most commonly used as a "B ." branch to self instruction in (dummy) exception handlers.
Therefore I _believe_ the above line means to create a data value evaluating to "FooEntry minus current address plus current address"... = FooEntry :)
I'm not entirely sure why one would do this, perhaps to obfuscate the FooEntry symbol?
Hi RonanThanks for answerI found this in Qalcomm ThreadX moduleThis create header of the BIN from ELF for relocations
and the question "...why one would do this..."I compile:
foo // = 0x78000000 is ro_base (-ro)DCB 0,0,0,0,0,0,0 // 7 zeroesDCB foo // = 0x78000007DCB foo - . + . // = 0x00000008 DCB foo // = 0x78000009
"- . + ." it seems as current address minus ro_base